Apparatus for filling bags



Feb. 4, 1964 B. J. scoTT APPARATUS FOR FILLING BAGS Filed Oct. 14, 1960l mDwwmma EDDO 1I.

IN V EN TOR.

B. J. SCOTT Arofwx/Ews a S uw oF n mu wo Tj.

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United States Patent O 3,120,239 APPARATUS FOR FILLNG BAGS Billy J.Scott, Borger, Tex., assigner to Phillips Petroleum Company, acorporation of Delaware Filed st. 14, 196th, Ser. No. 62,691 4 Claims.(Cl. 177-80) This invention relates to improved apparatus for fillingporous containers with powdered materials.

U.S. Patent 2,799,455, issued July 16, 1957, to Carter discloses a bagfilling apparatus with which this invention is concerned. The machine ofsaid patent employs a reduced pressure or partial vacuum within a bagenclosing shroud to draw and compact finely divided material into thebag. After a small portion of bag capacity is filled with the powderedmaterial in this manner, the pores of the bag become at leas-t partiallyplugged with the material. To overcome this, a vacuum line to the shroudis closed and air is vented into the shroud thru a valve so as topartially restore the pressure in the shroud and cause air to enter thebag, thereby removing powdered material from the wall of the bag andunplugging the pores or interstices in the wall so that incrementalfilling of the bag can ybe continued by repeating the cycle of reducingthe pressure in the shroud, injecting material into the bag, and againcutting off the flow of material and increasing the pressure in theshroud.

An Iapparatus made in accordance with the Carter patent, bearing thelabel, Serial No. 217, Model VB, was obtained from Carter EngineeringCompany, Danville, Illinois. This machine was used for a substantialperiod in the packaging of loose carbon black and proved verysatisfactory except that the vacuum control (device 165' in FIGURE 6 ofthe drawing) failed to opera-te and open the lling valve (valve 13? ofFIGURE 2) in the conduit leading from the `feed hopper to the fillingnozzle. Vacuum control device 165 senses pressure in the shroud 40 thrua conduit (not shown) leading from the shroud to the control and it wasfound that, after extended use, the conduit became plugged with carbonblack so that the control device became inoperable in that it could notsense the changes in pressure within the shroud.

An improved con-trol arrangement for the apparatus was devised and theapparatus, revised in accordance with the control arrangement of theinvention, has worked continuously over extended periods without anyoperating difiiculties and shu-tdowns caused by failure of the controls.The control arrangement of the invention is described herein.

Accordingly, the principal object of the invention is to provide animproved apparatus for incremental filling of porous containers withpowdered materials. Another object is to improve the control arrangementof the bag filling appara-tus of above-identified patent. Other objectsof the invention will become apparent upon cons-ideration of theaccompanyin-g disclosure.

The invention Iwill be best understood by reference to the accompanyingschematic drawing of which FIGURE l is an elevation of a Ibag fillingmachine in accordance with the invention; FIGURE 2 is a plan view takenon the line 2 2 of FIGURE l; and FIGURE 3 is a view of the circuitry andcontrols employed in the automatic operation of the filling machine.

Referring to FIGURES 1 and 2, a shroud 1li is suspended from a weighingdevice 12. which is supported from a frame (not shown). Support rod 14is pivoted on beam 16 which -is supported by fulcrum 18. Weight ZtlI isadjustable along beam 16 to control the total filling weight of the bag.Upon filling of the bag to the predetermined weight, beam 16 actuatesweight switch WS so as to open 3,120,289 Patented Feb. 4, 1964 itscontacts which are in an electrical circuit designed to terminate thefilling cycle.

Filling nozzle or spout 24 extends into the upper end of shroud 1li andis provided with pneumatic sealing device 25 including seals 25 and 27for holding a bag on the filling spout in sealed relation with the mouthof the bag. Nozzle 24 connects by conduit means 28 with a supply hopper30. Pneumatic material-fill-valve 32 in conduit 28 controls the liow ofpowdered material into the feed nozzle. A Vacuum line 34 containingpneumatic valve 36 connects with the shroud and iwith a vacuum source(not shown) for reducing the pressure therein. An air inlet or reliefline 38 connects with the shroud yand -is provided with pneumatic reliefvalves `4() for decreasing the vacuum in the shroud.

Shroud 10i is divided diagonally into two sections which are sealedalong plane 42. Section 43 is relatively fixed and section 44 is pivotedat hinge 46 so that section 44 ifunctions as the door of the shroud. Anarm 48 is fixed to door 44 and is pivotally connected with pneumaticopening and closing device Sti which is pivotally connected with arm 52.Door switch DS closes contacts in an electrical circ-uit upon closing ofdoor 44 to start the filling `sequence as described hereinafter.

The device thus far described is substantially disclosed in said patent.In addition lto the apparatus described herein, the Carter deviceincludes a -vent valve 134 which has been found to be unnecessary infilling a porous bag with powdered material. This valve is intended toaid in inflating the bag after insertion on the filling spout and afterapplication of vacuum to the shroud. However, since a lbag is partiallyfilled with air when it is placed on the filling spout, the evacuationof air from the shroud outside of lthe lbag adequately expands the bagfor the incremental filling which follows.

The controls for operating the device thru a complete lling sequence orcycle are shown in FIGURE 3. Leads L-l and L-Z connect with a suitablepower source such as a 11()1 volt 60 cycle alternating current source.The contacts of WS `are normally closed and are not opened until theweight of the material within the bag being filled causes the weighingdevice 12 to open the contacts of the switch. Contacts RHI are alsonormally closed. All other switches and relay contacts are shown intheir open state as they exist prior to commencing of the automaticfilling cycle.

A start push button 60 which is normally open and a normally closed stopbutton 62 are connected in series with the contacts WS and the coil of arelay RA. Contacts RA1 of relay RA are connected in shunt across startbutton of; so as to form a holding circuit for relay RA, once thecontacts of push button 69 have been momentarily closed to energize therelay. Contacts RAZ of relay RA are connected across the leads of thepower source in series with contacts WS and the coils of solenoids SA,SB, SC, and SD. Thus, when contacts RA2 are closed, the solenoids areenergized thru contacts WS.

Solenoids SA and SB are connected to actuate separate pneumatic 3-wayvalves 64 and 66, respectively, which are operable to couple alternatelypressurized fluid or atmospheric pressure with pneumatic door actuator5f). As described hereinbefore, door actuator Stiry is positioned toeffect opening and closing of shroud door 44. In the relation shown in'FIGURE 3, the valves controlled by solenoids SA and SB are disposed toretain the door actuator in its fully opened position. Upon energizationof solenoids SA and SB, the valves 54- and 66 move to couple pressure tothe left side of the actuator piston and vent the right side of thecylinder to atmosphere. This action closes door 44 for the successivesteps of the filling sequence.

Solenoids SC and SD are connected to actuate pneumatic 3-Way valvesd and'79, respectively, so as to either pressurize filling spout sealmechanism 25 (separate seals 26 and 27) or depressurize the same byventing the seals to atmosphere and releasing the clamping actionthereof. As shown, the seals are depressurized.

As pneumatic actuator closes the shroud door 4d as the result ofenergization of solenoids SA and SB, door switch DS is closed so thatthe contacts are connected in series with the operating coil of relay RBforming a circuit from L-2 thru WS, switches 62 and DS, and relay RB toL-l. One pair of contacts RB1 -of relay RB are connected in shunt aroundswitch DS to form a holding circuit for relay RB.

Upon energization of relay RB, contacts RBZ are closed so as to starttimer 72. Timer 72 is connected in series with contacts RB2 .across thepower source. This timer is operable to energize relay RC after a shortperiod such as l to 3 seconds. This timer may be of any suitableconstruction but is preferably an electronic timer and is provided witha dial 74 which can be set for the time delay before energizing relayRC. Contacts RC1 of relay RC are locking contacts which when closed byenergization of relay RC remain locked in closed position until unlockedby relay RH, described hereinafter. Closing vof contacts RC1 establishesa complete circuit from L-Z thru WS, RC1, and solenoids SF and SG toL-li. This circuit energizes solenoids SF and SG which open vacuum valve36 and close the relief valve 40, respectively so as to reduce thepressure in shroud for the first incremental filling.

When circuit is established thru contacts RC1 a circuit is alsoestablished thru timer 76 which is provided with dial 78 for adjustingthe time delay of this timer in actuating relay RH. The time delay isregulated so as to permit the predetermined reduction of pressure in theshroud before opening ll valve 32 for incremental filling of the bag.Upon actuation of relay RH contacts RH1 are opened to stop timer 72, andcontacts RH2 are closed to energize solenoid SH which opens the materialll valve 32. After a selected time to provide the desired fillingincrement, timer i6 de-energizes relay RH so that contacts RC1 areunlocked and contacts `RH1 are released to again close and make Contactto start timer 72. This action again energizes relay RC and closescontacts RC1 to repeat the steps of the incremental filling cycle.

The time delay between unlocking of contacts RC1 and re-energizing relayRC should be very short for most ellicient operation so as to permitonly partial reestablishment of atmospheric pressure in the shroud. Thispartial restoration of pressure Within the shroud causes flow of airthru the walls of the bag so as to remove powdered material from thepores and the inside wall of the bag above the lled level. This allowsair Within the bag to be displaced and sucked thru the bag wall duringthe ensuing evacuating step resulting from energizing relay RC andclosing of contacts RC1 so as to energize solenoids SF and SG.

The setting of timer 76 so as to regulate the period during whichcurrent is passed thru relay RH to maintainl contacts RH2 closed,determines the till period or the time during which valve 32 is open.This period depends upon the regulation of the aforesaid time intervaland controls the size of the increment of carbon black or other powderedmaterial which is delivered tov the bag during each cycle of successiveoperation of timer 72, relay RC, timer 76, and relay RH. Timer 72 isstopped and reset each time relay RH opens contacts RH1. Timer 76 resetsitself upon de-energizing relay RH and unlocking contacts RC1. y

Valves 32, 36, and 40 are conventional pneumatically operated diaphragmvalves. Opening and closing of this type valve is effected by regulatingthe flow of pressurized fluid (air) to one side of the diaphragm withinthe valve.

amazes Pressure on the diaphragm of the valve maintains the valve inclosed position whereas release of pressure or application of vacuumopens the valve.

From the foregoing disclosure it can be seen that the controls of theinvention in combination with the disclosed structure provide a positivetime cycle of automatically operating of three valves controlling thepressure reduction in the shroud (valves 36 and d@ and the introductionof powdered material to the filling spout (valve 32). The system of theinvention avoids any possibility of plugging of the vacuum line from theshroud to vacuum control instrument of the Carter device by completelyeliminating this control and its associated conduit. The invention alsoeliminates other apparatus elements, such as relays with theirassociated contact points, and it simplifies the circuitry required forautomatic operation of the bag ller.

Certain modifications of the invention will become apparent to thoseskilled in the art and the illustrative details disclosed are not to beconstrued as imposing unnecessary limitations on the invention.

l claim: Y

l. Apparatus for incremental filling of a bag with powdered material,comprising in combination, a shroud substantially scalable to theatmosphere; a illing spout extending into said shroud sealed therewithand pro-y vided with means for sealing to the mouth of a bag; a supplyvessel connected by a delivery conduit with said spout; a lirst valve insaid delivery conduit; a gas inlet to said shroud; a second valve insaid gas inlet; a vacuum line leading into said shroud; a third valve insaid vacuum line; first means including a first electrical circuit forsubstantially simultaneously opening and holding said third valve openand closing and holding said second valve closed for a selected timeinterval; second means, comprising a second electrical circuit and aiirst timer therein actuated by said lirst means after a short timeinterval to effect lpressure reduction in said shroud, for opening andholding said first valve open while said first means is functioning tohold said second and third valves and maintain said pressure reduction,said second means functioning for a short time interval before closingsaid iirst valve and reversing said second and third valves to preparefor a second cycle of incremental filling.

2. The apparatus of claim l wherein said shroud is provided with anaccess door and said rst electrical circuit is energized by a switchmounted on said door so as to close upon closing said door.

3. Apparatus for incremental filling of a porous bag with powderedmaterial, comprising in combination, a shroud sealable to theatmosphere; a tilling spout extending into said shroud and sealedtherewith; means on said spout for holding the mouth of a bag in fillingposition in sealed relation thereto; a delivery conduit connected withsaid spout; a lirst pneumatic Valve in said conduit; a gas inlet to saidshroud having a second pneumatic Valve therein; a vacuum line connectedwith said shroud having a third pneumatic valve therein; a firstsolenoid operated three-way valve connected by a pneumatic line to saidfirst valve; a second solenoid operated three-way valve connected by apneumatic line to said second valve; a third solenoid operated three-wayvalve connected by a pneumatic line to said third valve; a rstelectrical circuit including'the solenoids of said second and thirdthree-way valves; a second electrical circuit including a irst timer, afirst relay actuated by said timer, and normally closed contacts in saidsecond circuit; locking contacts in said rst circuit responsive to saidfirst relay for closing the circuit thru said solenoids; a third circuitconnected with said rst circuit, including a second timer, a secondrelay actuated by said second timer, and the solenoid of said rstthree-way valve, said second relay functioning to open said normallyclosed contacts and stop said rst timer when energized and to unlocksaid locking contacts when de-energized, and said second timer closingsaid third circuit thru the solenoid of said first three-way valve aftera short predetermined time to start filling.

4. Apparatus for incremental lling of a porous bag with powderedmaterial, comprising in combination, a shroud sealable to the atmosphereand providing a chamber for a bag for lling and an access door forintroduction and removal of said bag; a first switch mounted so thatclosing of said door closes said switch, weighing means supporting saidshroud and provided with a second switch for terminating the lling cycleupon introduction of the desired weight to said bag; a feed spoutdisposed within the upper section of said shroud and provided with meansfor holding the mouth of a bag in sealed relation therewith for iilling;a feed conduit connected with said feed spout having a irst valvetherein 6 actuatable to open and close said conduit to iiow of feed; aninlet to said shroud having a second valve therein for admitting air tosaid shroud; a vacuum conduit connected with said shroud having a thirdvalve therein; iirst means, including a timer, actuatable in response toclosing of said rst switch for opening said third valve and closing,7said second Valve; second means, including a timer, actuatahle by saidiirst means after a predetermined time delay, for opening said firstvalve for a lling increment, said second means operating to close saidfirst valve after a predetermined short lling period and reverse thepositions of said second and third Valves.

References Cited in the le of this patent UNITED STATES PATENTS2,799,465 Carter July 16, 1957 UNITED STATES PATENT OFFICE CERTIFICATE0F CORRECTION Patent No 3B 120289 February 4 1964 Billy J Scott It ishereby certified that error appears in the above numbered patentrequiring correction and that the Said Letters Patent should read ascorrected below.

Column 4 line 32 for "including" read comprising same line 32, after"circuit" insert including actuating means for said second and thirdValves me; line 37 after "therein" insert said second circuit and timerbeing in circuit with and line 38V after "shroud V insert --1 .Saidysecond circuit including actuating means responsive to said timer forsaid first Valve -f-e,

Signed and sealed this 23rd day of June 1964i7 (SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Commissioner of Patents AttestingOfficer UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nom1207289 February 4f, 1964 Billy Jo Scott It is hereby certified thaterror appears in the above numbered patent requiring Correction and thatthe said Letters Patent should read as corrected below.

Column 4 line 32Y for "including" read f comprising same line 32, after"circuit" insert including actuating means for said second and thirdvalves ee; line 37, after "therein" insert said second circuit and timerbeing in Circuit with and line 38Y after "shroudf" insert Sad secondCircuit including actuating means responsive to said timer for saidfirst valve Signed and sealed this 23rd day of June 1961io (SEAL)Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attestlng Officer Commissioner ofPatents

1. APPARATUS FOR INCREMENTAL FILLING OF A BAG WITH POWDERED MATERIAL,COMPRISING IN COMBINATION, A SHROUD SUBSTANTIALLY SEALABLE TO THEATMOSPHERE; A FILLING SPOUT EXTENDING INTO SAID SHROUD SEALED THEREWITHAND PROVIDED WITH MEANS FOR SEALING TO THE MOUTH OF A BAG; A SUPPLYVESSEL CONNECTED BY A DELIVERY CONDUIT WITH SAID SPOUT; A FIRST VALVE INSAID DELIVERY CONDUIT; A GAS INLET TO SAID SHROUD; A SECOND VALVE INSAID GAS INLET; A VACUUM LINE LEADING INTO SAID SHROUD; A THIRD VALVE INSAID VACUUM LINE; FIRST MEANS INCLUDING A FIRST ELECTRICAL CIRCUIT FORSUBSTANTIALLY SIMULTANEOUSLY OPENING AND HOLDING SAID THIRD VALVE OPENAND CLOSING AND HOLDING SAID SECOND VALVE CLOSED FOR A SELECTED TIMEINTERVAL; SECOND MEANS, COMPRISING A SECOND ELECTRICAL CIRCUIT AND AFIRST TIMER THEREIN ACTUATED BY SAID FIRST MEANS AFTER A SHORT TIMEINTERVAL TO EFFECT PRESSURE REDUCTION IN SAID SHROUD, FOR OPENING ANDHOLDING SAID FIRST VALVE OPEN WHILE SAID FIRST MEANS IS FUNCTIONING TOHOLD SAID SECOND AND THIRD VALVES AND MAINTAIN SAID PRESSURE REDUCTION,SAID SECOND MEANS FUNCTIONING FOR A SHORT TIME INTERVAL BEFORE CLOSINGSAID FIRST VALVE AND REVERSING SAID SECOND AND THIRD VALVES TO PREPAREFOR A SECOND CYCLE OF INCREMENTAL FILLING.